Where Should We Look for Ancient Biosignatures on Mars in 2020?

One of the great successes of the Curiosity mission to Mars is that the rover landed at what turned out to be a goldmine of a location.

The mission has once and for all determined that the planet was habitable at least during its early days, that it contains the organic building blocks of life, and that liquid water ran and formed lakes. And this leaves out the more basic Mars science that will some day produce new headline results.

The process of anointing a successor destination for NASA’s 2020 rover mission to Mars has been going on for several years now, and the field was narrowed to three possibilities earlier this year.

Because some of the primary goals of the 2020 mission differ from those of the Curiosity mission, the potential landing sites are unlike Gale Crater and all share certain features that are, not surprising, promising in terms of the new goals. What’s new is the requirement that the 2020 mission will search for biosignatures of life in the ancient rocks and to identify, pick up and store rock samples for later return to Earth.